CL for testing on Win.

base/trace_event/trace_event_impl.cc

Index: base/trace_event/trace_event_impl.cc
diff --git a/base/trace_event/trace_event_impl.cc b/base/trace_event/trace_event_impl.cc
index 4ab0d358f9d202dd31ba6418b098da6751348e05..2982b000b76a7adbae2b150492c3653ab4d1afd4 100644
--- a/base/trace_event/trace_event_impl.cc
+++ b/base/trace_event/trace_event_impl.cc
@@ -185,7 +185,10 @@ void TraceEvent::Reset() {
 
 void TraceEvent::UpdateDuration(const TimeTicks& now,
                                 const ThreadTicks& thread_now) {
-  DCHECK_EQ(duration_.ToInternalValue(), -1);
+  if (duration_.ToInternalValue() != -1) {
+    LOG(ERROR) << "ssid duration is already set " << flags_ << " " << timestamp_ << " " << name_ << " " << (parameter_copy_storage_.get() ? *parameter_copy_storage_.get() : "no param") << " " << TraceLog::GetCategoryGroupName(category_group_enabled_);
+  }
+  CHECK_EQ(duration_.ToInternalValue(), -1);
   duration_ = now - timestamp_;
 
   // |thread_timestamp_| can be empty if the thread ticks clock wasn't